Sulfur-burning furnace.



. GLARK.

Patented 1111115, 1910.

2 SHEETS-SHEET l.

IT EEEE r C. B. CLARK. SULFUR BURNING FURNAGE. APPLIGATION FILED AUG. 7, 1908.

952,99, Patented Mar. 15, 1910.

2 SHEETS-SHEET 2 exact description, reference being had to the entran srarns CHARLES B. CLARK, 0F BANGGR, MAINE.

SULFUR-BURNIN G FUR/NACE.

-Specification of Letters Patent.

rammed nal-.1.5. icio;

Application filed August 7, 1908. Serial No. 44"r' .?v50.A

accompanying drawings, formingfa. part of this specification, 1n explalning its' nature,

My invention relatesto an improvementl in sulfur burning .furnaces 'of that kind which are designed especially for., making sulfur dioxid to' be usedrin connection with the sulfite process of manufacturing wood.

pulp, and a furnace, also, especially adapted `-forA practicing the process described in my copending application for Letters Patent of the United States, filed June 8, 190'8, Serial No, 437,213, and appertaining to the same subject matter.

Among the essential objects of my invention are'z-to providea furnace capable 0f producing a large amount of sulfurous acid gas; to providea furnace which in order to operate properly will not necessitate ,the employment of any auxiliary power to revolve or agitate it, but which furnace will be self.

acting, or, in other words, complete vin itself; to provide a furnace in which a small amount of sulfur trioxid will be produced relatively to the sulfur dioxid produced therein; to provide for the conversion of any sulfur trioxid that ma form in the furnace into sulfur dioxid prior to its delivery or eXit from the furnace through the pipes of any system in. connection with which the furnace is used; and to proyide also for the consumption and conversion into sulfur dioXid of any vaporized sulfur that may be unconsumed in the main body of the furnace or chamber where the sulfur is initially burned. o

My invention will be understood by reference to the drawings in whichl Figure 1 shows the furnace mainly .in cross vertical section. Fig. 2 shows an elevation of the front end of the bbody of the furnace. Fig. 3 is a section on the line 3-3 of Fig. 1. Fig. 4 shows mainly -in vertical section a slightly modified embodiment of the furnace'. Fig. 5 is a section on line 5-5 Vof Figa.

' 1 represents the main body of thefurnace or .burner proper.

2 is a combustion chamber which connects with the rear-endV of the body 1 o f the furnace by a connecting 4pipe 3.

The main body of the furnace comprises a structure made preferably arched, with walls-formed mainly of Iirebrick or other heat-retaining substance, preferably coated with-a layer of asbestos 4, as is also the floor ofthechamber under the furnace body;

In Figs. 1-3, where I have represented the first embodiment of my invention, I have shown the face 5 of the furnace body as being made of metal plate for the reason that more convenient access is had through such a place into the interior of the furnace than through a wall formed of bricks. I prefer, however, as shown in Figs. 4 'and5, where there is represented another embodiment of my finvention, that even the front wall of the -furnace body bemade of irebrick or other heat-retaining substance.

The combustion chamber 2 comprises a structure that preferably rises some distance above the main body ofthe furnace. This chamber like the bodyof the furnace is also preferably made of irebrick or other heat-retaining and acid proof material. The gases from the main body l of the furnace enter the combustion chamberby way of the connecting pipe 3 and pass out of the chamber by way of an'outl'et pipe 6.

Located within the'chamber of themain body l of the furnace and supported by the sides thereof is a series of arches 7 made preferably of firebrick. These arches support a pan 8 raised above the floor of the chamber a sufficient amount to permit of the chamber being cleaned out between and underneath the supporting arches.

In the front of the body of the furnace emptying into the tpan 8 is what maybe termed a `hopper 9 or into this hopper. the

sulfur'to be burned is first deposited from outside the furnace from whence it passes into the pan 8. The sulfuri's introducedinto the burner by an opening 10 located in the faceplate 5, which opening controlled a slide l1.4 Near the bottom of the face l plate is an ope-ning 12 aifording au inlet into the interior of 'the body ofthe furnace and providinga cleanout. This opening is Acontrolled by doors 13.

' Air is admitted into the interior o f the furnace body by wayl of the openings 14 formed in the side walls of the furnace body.

ya little abovelthe floor thereof. These open- 'ings are controlled from the outside. by`

means of slides 15 by which` a graduated amount of air may be admitted throughy the through it to mingle intimately .with the afire of burning sulfur is made preferablyv `placed in the top thereof.

gases passing out of the body of the furnace into the combustion chamber. The open end of this pipe is controlled loutside the combustion chamber by a gate or slide 19. At or near the base of the combustion chamber another air inlet 2Q is also,v referably, provided.' This opening or in et is controlled from outside the combustion chamber by means of a gate or slide 21.

. To determine the temperature in the combustionchamber a pyrometer 22 may be -Thel operation is' as follows z--The hopper t9-having been filled with sulfurand a portion thereof having passed into the pan 8 lon the iicor of the furnace body beneath the pan. The'heat.'causes the sulfur in the vpan to melt and the an. soon becomes filled witlnhotmelted su fur. As the sulfur melts in the pan fresh sulfur Will pass into the pan from the hopper9 thereby tending to, keep the pan full of melted sulfur. Thepanv being lkept thus full, the sulfur tends to overflow the pan and drop onto the floor or hearth'of the burner Where it continues to burn With the effect that the sulfurvburning on thefio'or iskept in a condition of constant agitation by thesulfur dripping from 7 the pan. When the heat vWithin the chamber of the burner', retained as it is bythe b riclrl wallsrof the chamber; becomes sufficiently -high a considerable amount of sulfur will also burn in the pan itself or become vaporized therein. The heat Will also cause more or lessrof the sulfur in the hopper to' become melted before passing into the pan. The effect and .Working of all this is similar tothat obtainedl with a revolving furnace but with the advantage that no poweris required to operate the furnace. Though a large amount Aof sulfur, dioxid will be formed in themainbody or burner of the .'.furna`ce,' yet there Will also be formed sul- Afur trioxid and unconsumed vaporlzed sulfur which Iwill pass out of the chamber 'of .the burner and enter the combustion chamber. These products are taken care of acy cordmgelto theprocessdescribed in my said ber.

eeaoaa applicationa the l'sulfun'.vaijior,l being consumed and the sulfur trloxid converted into sulfur dloxidv and oxygen. The sulfur vapor is consumed through the admission.

of air tov it by Way of 'the vair inlet pipe 18 which mingles with the vaporized sulfur 1n the" chamber of the `burner Where its consumption is begun and-passes with itv intothe combustion chamber Where the combustlon of the vapor is completed. The sulnance of a substantially constant and proper temperatiirc within the combustion chamber, or in other Words, sucha temperature as Will convert sulfur trioxidinto sulfur dioXid and oxygen. This temperature is referred to in my said application as 1one approximating 1100O C., .it being inadvisable'- to maintain a temperature below 950. C.,nor

. above '1200o C; though excellent results are obtained at a temperature maintained at 'about 1150O C. iNow by-the entry of air through the inletI pipe 18 supplemented by the opening or inlet 2,0 not only. can a suffiair for burning the vaporized sulfur, orif for the same purpose an excess of air is let in through the air inlets or openings ,T 1n

`the body of the furnace it is impossible to maintain such temperature in the combus- 4fuil trioxid is decomposed or converted into 'sulfur dioxid and oxygenby lthe maintecient amount .of air be 'introduced to effect vthe air opening 20vris relied upontolet in tion chamber as Will decompose the sulfur trioxidand therel is danger, also of converting much of the sulfur'dioxid into sulfur trioxid. The amount of air admitted through the pipe 18 and. opening 2O may be regulated byf the gates or4 slides 19,` 217 1 espectively.

Referring now to the further embodiment of my invention shown in Figs. 4land 5: 23 represents the body of the furnace. This is substantially likey the body 1 of the furnace shown in 4Fig. 1. 24 is the ,combustion cl1amber,'the same as before described. y 25 is the passage connecting the chamber inside thev body ofthe furnace with` the linterior of the combustion chamber. 26 represents the outlet from the combustion cham- Inside the body 23 of the furnace and extending longitudinally along the floor of the chamber thereof is a conduit 27 supporting a pan 28 4formed in the. top side thereof. Emptying into this pan isanti'nclined hopper 29 which entends through the conduit 27. is an air inlet ipe 31 which extends through the combustion chamber. The

openend of thisl pipe outside the combustion chamber is controlled by a 4slide 32. .The air which is let in throughthe pipe 3l into the conduit passes. out o f -the same into the chamber of the body 23 by Way of the auxiliary passages 33 cut through the Wall of the conduit and-entering the chamberjust above' v'the bottom thereof. Attention is also directed to the drumA 34evvhich lies back of' the vcombustion chamber andvjust adjacent 'to the Vair inlet pipe 31 .extending through the 'chamber andinto vvhich'drum hot gases from the combustion chamber are -directed A from the outlet. pipe 26. lThedrum is 4preferably made of Wrought iron in vorder to withstandgthe excessive heat to which -it is subjected.

The adaptation of the,l arts and operation of the furnace is as fo lows The sulfur fis de osited inthe tubeor hopper 29 Where it ine ts and runs dcvvn into the pan Q8. In

ythe lirst instance, if the furnace is started lup cold, a small amount of sulfur is placed inthe 'panandthere ignited for melting the sulfur in the tube.v If, however, the

furnace has notl been shut down forptoo long a. time, theheat retained in it is sufficient to In'elt the sulfur in the tube and "cause it to' run into the. pan.

e `The sulfur burns in the pan and fa very rge amount vaporizes therein. It frequently overflows. the pan' vand burns on the hearth. (In fact; the heat- `is so .l intensewithin the chamber that the sulfur -Will burn anywhere'withinthe chamberjeither in the pan or outside of it, but t-he majorityv of it being burned in the pan.

Theair for'burning the sulfur is a heated Nair vintroduced by Way of the pipe 31A which extends through theanterior of the combu s.

tion chamberfand connects with the Aconduit 27 beneath the pan, the airpassing out into the main chamber ofthe body of the furnace by Way ofthe anxiliarypassages 33. vNOW the advantage of introducing a heated air into `the chamber in the manner above de `scribed resides 4in vthe fact-that I am enabled" not only to induce the initial burning of the sulfur, but Iam-enabled also to ad- `mit suiicient air" to burn thevaporized sulfur and, at the same time to maintain a proper rtemperature lin the combustion chainber 'for thelpurpose before described.

Another advantage' of admitting a heated 'air into the main' body ofA the furnace toin.- duce the initial burning of the sulfur resides in they fact that ver, little sulfur trioxid will be formed. .Sul r trioxid cannotwell beproduced be'tvveen 4,20 and 1100` degrees- C., and so vby burning 'the sulfur .,in air heated above 4203 C., practically only sulfur dioxid will be obtained. Should sulfur tri- .oxid lbe formed by the heat notJ quite reaching this pointthe vheat retained bythe combustion chamber will as before described decompose it into sulfur dloxidl and oxygen. The adva-ntageof having the hot gases from the combustion wchamber pass into the drum 34 lying just adjacent to the air inlet pipe 31 'resides in the fact that the air before it enters the pipe 31 must Y pass around 4the drum and accordingly-becomes less andless heatedv before entering theair inlet pipe, which I'have found to be of more or less practicalbeneiit. a v

What I clam'as my invention is 1. In a sulfur-burning furnace, tl e'combination of a burner in which the. sulfur is burned, va combustion chamber connecting therewith into which the gases and vapors from the burning sulfur are directed to pass and be confined before issuing from saidchamber, means Whereb air heated by the contents of the combustion chamber may be admitted to the'chamber of the burner for inducingeombustion therein and means also whereby air may be admitted for regulating the temperature ofthe contents of the combustion chamber, substantially as and for the purposes set forth.

2. In a sulfur-burning furnace, the combination of a burner in which 'the sulfur is burned, a combustion .chamber connecting with said burner for receiving the hotv gases andyapor from the burning sulfur, said combustion chamber having an opening therein by which air may be admitted into said chamber, and an airinlet pipe'within said Achamber in .communication with the outside thereof for directing air passing through said pipe and heated by the con tentsof said chamber into the hot gases and vapor entering said chamber.

' 3.-' In a sulfur burnin furnace, the combination of the body of t e furnace having a 'chamber in Whichithe sulfur is burned, a

combustion chamber connecting. with said body for receiving the hot gases and vapor from the burning sulfur, and an air inlet pipe of the furnace passing through said combustion chamber. v 4:. In a sulfur burning furnace, the-combination ofthe body of the'furnace having a chamber in which the sulfur is burned, a

,combustion chamberv connected with said bod to receive ,the hot gases and .vapor from the urning sulfur, said combustion chamber having an outlet; an air inlet for regulating the temperature in said chamber, and an air inlet pipe passing through said chamber for delivering air into the chamber of said body of the furnace.

5. In a sulfur burning furnace, the combination vvith a burner having a chamber in which the sulfur is burned', of means whereby'- air may be supplied i'or eHiecting an chamber independent of said chamber ot the 1n1tial.,bLirning oi" the sulitur, a combustion burner and 111to whichcombustlon chamber chainber-independent of said chamber of the g the gases and vapors `from the initlal burnburner and into which combustion chamber the gases-andwvapors irom the initial burning of the sultur are directed to pass, means whereby hot air may be supplied to commingle with the gases and vapors ofthe burning sulfur for inducing a consumption .of the vaporized sulfur and whereby, also, a

substantially constant high temperature may be maintained in the combustion chamber, and means whereby cool air `may be admitted to said combustion chamber for-controlling the temperature of the gases and vapors therein as occasion may require.

6. Ina sulfur burning furnace, the combination of the body of the furnace having a .chamber in whichA the sultur is burned, a

combustion chamber connecting therewith into which the gases and vapor from the burning sulliunare directed to pass, said combustion chamber having an outlet, and an air inlet pipe passing through said coinbuston-chamber whereby the air entering 'the pipe may be heated by the gases in said combustion chamber, substantially as and for the purposes set forth.

, 7. In a sulfur burning furnace, the coinbination of the 'body ofl the furnace having achamber in which the sulfur is burned, an air receiving' conduit locatedfin said chamber and opening into the same, a combustion chamber connecting with the chamber of said body into which the gases and vapor from the burning sulfur are directed to pass, said combustion chamber having an outlet and an air inlet' pipe passing through said combustion chamber and connecting with said conduit.

8. In' a sulfur burning furnace, the com'- bination with a burner having ,a chamber in which the sulfur is burned, of means whereby air may be supplied for effecting an ini-A tial burning of the sulfur, a combustion ing ot' the sulfur are directed to pass, means whereby airheated by the hot gases and products of combustion-may be supplied to comminglewith the gases and vaporsof the burning sulfur for inducing a consumption ot' the vaporized sulfur and whereby, also, a substantially constant high temperature Amay be maintained in the combustion chamber, and means whereby cool air may be ladmitted t0 said combustion chamber :for

controllingthe temperature of the gases and lvapors therein as occasion may require.

5). ln a sulfur-burning furnace, the body of the furnace having achamber in which the sulfur is burned, a' pan located in said chamber and elevated above the hearth thereof, said pan being of such size and relative disposition that melted sulfur in said pan may flow over the edge thereof onto said hearth, an air-receiving conduit located in the bottom of said chamber and opening laterally into said chamber, and means whereby air may be supplied to said con duit.

10. In a sulfunburning furnace, the combination with the body of the furnace having a chamber in which the sulfur is burned, an. air-receiving conduit located Within said chamber vand opening into the same, a combustion chamber connecting With the chamber of said body and into which `the gases and vapor of the burning sulfur are directed to pass, said combustion chamber having an outletand an air inlet, and an air inlet pipe passing through said combustion chamber and connecting with said conduit for supplying air thereto.

CHARLES B. CLARK. 

